The 90-Night Rule and Fire Safety: What Short-Term Let Hosts Get Wrong

If you let your property on Airbnb and assume fire safety law does not fully apply because you stay under the 90-night limit, you are taking a serious legal risk. Hosts have faced unlimited fines and criminal prosecution under the Regulatory Reform (Fire Safety) Order 2005 for exactly this mistake. The 90-night rule does not give you a fire safety pass. It never did.

What the 90-Night Rule Actually Is

The 90-night rule comes from Section 25 of the Deregulation Act 2015. It applies only in Greater London and only as a planning exemption. It says that London homeowners can let their entire home as short-term accommodation for up to 90 nights per calendar year without needing planning permission for a change of use.

That is it. That is the entire scope of the rule. It is a planning instrument, not a fire safety one. It says nothing about smoke alarms, fire doors, electrical certificates, or fire risk assessments. It exists to stop the permanent loss of residential housing stock, not to define what safety standards your guests deserve.

Outside London, the rule does not exist at all. Hosts in Manchester, Bristol, Edinburgh, or anywhere else in the UK have no equivalent 90-night exemption. Planning status for short-term letting outside London is assessed by local authority policy on a case-by-case basis. There is no threshold that makes you exempt from anything.

The Myth That Gets Hosts Into Trouble

The problem is that many hosts conflate the planning exemption with a broader sense of operating informally. The reasoning goes: I am under 90 nights, so I am technically still a residential property, and commercial fire safety law does not apply to me. That logic has no basis in fire safety legislation.

The Regulatory Reform (Fire Safety) Order 2005 does not reference planning status, use classes, or night thresholds. It has one trigger: are you providing accommodation to paying guests? If the answer is yes, even once, you are subject to the RRO 2005. Planning permission is a separate matter entirely, governed by separate legislation, enforced by a different authority.

Staying under 90 nights may keep your local planning department off your back in London. It does nothing to satisfy your fire safety duties.

What the RRO 2005 Actually Requires

The Regulatory Reform (Fire Safety) Order 2005 applies to all non-domestic premises in England where people work, sleep, or pay to stay. The moment a guest pays to sleep in your property, you become the "responsible person" under the Order. That status does not switch on at night 91. It switches on at booking number one.

As the responsible person, you have a legal duty to carry out and record a suitable and sufficient fire risk assessment, review it regularly, and act on its findings. A standard domestic smoke alarm check is not a fire risk assessment. The assessment for a short-term let must account for transient occupants who are unfamiliar with the layout of your property and would not know where to go in an emergency. That changes the risk profile significantly compared to a home you live in yourself.

The Fire Safety Act 2021 extended and reinforced these obligations. Non-compliance carries unlimited fines. In serious cases, it carries imprisonment.

The Specific Duties

Under the RRO 2005, short-term let hosts must have in place:

• A written fire risk assessment, reviewed at least annually and whenever significant changes are made to the property or its use
• Interlinked smoke and heat alarms in bedrooms, living areas, and along escape routes. Basic standalone domestic alarms (Grade F) are not sufficient. Grade D1 or D2 mains-powered units are the minimum standard for a property with paying guests
• Emergency lighting along escape routes and in bedrooms, so guests can find their way out in darkness or smoke
• Fire doors (FD30s) on rooms that lead onto protected escape routes
• A fire blanket in the kitchen as a minimum, and a fire extinguisher in any shared or common areas
• An EICR (Electrical Installation Condition Report), renewed every five years
• Clear fire safety information for guests, posted prominently in the property, covering escape routes and what to do in an emergency

For a detailed breakdown of alarm standards and placement, see the guide to holiday let smoke alarm and CO alarm requirements.

The 2026 Registration Scheme Removes Any Remaining Doubt

If there was any ambiguity about whether short-term let hosts needed to take fire safety seriously, England's mandatory STL registration scheme has removed it.

The scheme, which launched in 2026 under the Levelling Up and Regeneration Act 2023, requires hosts to confirm fire safety compliance as part of the registration process. You cannot register without it. You cannot legally operate without registering. Platforms are already requiring fire safety certification uploads before a listing goes live. Operating without registration carries fines of up to £5,000 per property.

For the full picture of what registration requires, see the guide to the England STL registration scheme 2026 fire safety requirements.

The 2026 scheme does not create new fire safety obligations. It simply makes clear that someone will now check whether you have met the obligations that already existed.

A Note for Hosts Outside London

Hosts outside London sometimes assume they have more freedom because the 90-night rule does not apply to them. There is no threshold to track, no automatic platform cap, and often less visible council scrutiny. In practice, this makes fire safety obligations more pressing, not less. There is no administrative nudge to keep you compliant.

The RRO 2005 applies equally in every part of England. A host letting a cottage in the Lake District for 20 nights a year has the same fire safety duties as a host letting a London flat for 89 nights. Planning status is irrelevant in both cases. The law does not care how often you let. It cares that someone is paying to stay.

Next Steps

If you are letting your property to paying guests, even occasionally, you need a written fire risk assessment. Not a checklist, not a quick scan of the smoke alarms — a proper assessment that covers your escape routes, your detection systems, your fire doors, and the specific risks created by guests who do not know your property.

FRASafe's holiday let fire risk assessment walks you through every area required by HMSO guidance. Complete it online in 30 to 45 minutes for £45. The resulting PDF is the document you need to satisfy the RRO 2005, satisfy your insurer, and register under the 2026 scheme.

The 90-night rule was never about fire safety. Now you know that, act on it.